Description of problem:
ipa-client-install --domain=testrelm --realm=TESTRELM -p admin -w <xxx>
--no-sssd
installs the client.

But it should check if nss_ldap package is available or if config files exist
and not proceed with the join, if LDAP cannot be configured.

we don't require the nss_ldap package because not using sssd is optional

note: related bug 746276

Version-Release number of selected component (if applicable):
ipa-client-2.1.3-8.el6.x86_64

How reproducible:
always

Steps to Reproduce:
1. With nss_ldap not installed, run cmd:
ipa-client-install --domain=testrelm --realm=TESTRELM -p admin -w <xxx>
--no-sssd


Actual results:
client is installed

Expected results:
message to indicate that nss_ldap pkg should be installed to allow --no-sssd
option

Additional info: